What is the main function of the fibula in the lower leg?

The main function of the fibula in the lower leg is to stabilize the ankle. The fibula runs parallel to the tibia, which is the larger and weight-bearing bone of the lower leg. While the fibula does not bear significant weight itself, it plays a critical role in providing structural support to the ankle joint. Its presence helps to maintain the lateral stability of the ankle, ensuring proper alignment and function during movement. This stabilization is crucial for activities such as walking, running, and jumping, where ankle integrity is necessary to prevent injuries.

The fibula also serves as an attachment point for muscles that control the movement of the foot and ankle, but its primary function in the context of the ankle joint is stability. Other answers pertain to functions that are either more relevant to the tibia or do not accurately reflect the specialized role of the fibula in the skeletal structure of the lower leg.